Remove outdated DTLS 1.3 test suppression

We broadly can receive NST now. Just needed to make sure the tests
actually flushed them.

Bug: 42290594
Change-Id: I7ab41b6af0e19eb548c52593cc99e787fedbdd41
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/73128
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Nick Harper <nharper@chromium.org>
diff --git a/ssl/test/bssl_shim.cc b/ssl/test/bssl_shim.cc
index 885e5fe..5a17c5c 100644
--- a/ssl/test/bssl_shim.cc
+++ b/ssl/test/bssl_shim.cc
@@ -1281,8 +1281,7 @@
     return false;
   }
 
-  if (GetProtocolVersion(ssl) >= TLS1_3_VERSION && !SSL_is_dtls(ssl) &&
-      !config->is_server) {
+  if (GetProtocolVersion(ssl) >= TLS1_3_VERSION && !config->is_server) {
     bool expect_new_session =
         !config->expect_no_session && !config->shim_shuts_down;
     if (expect_new_session != test_state->got_new_session) {
diff --git a/ssl/test/runner/handshake_server.go b/ssl/test/runner/handshake_server.go
index 9f90722..819fbc9 100644
--- a/ssl/test/runner/handshake_server.go
+++ b/ssl/test/runner/handshake_server.go
@@ -1395,6 +1395,9 @@
 		for i := 0; i < ticketCount; i++ {
 			c.SendNewSessionTicket([]byte{byte(i)})
 		}
+		if err := c.flushHandshake(); err != nil {
+			return err
+		}
 	}
 	return nil
 }